I have a 83 xl600. I got it as a basket case. I have it up an running with the stock jets. But the problem I have is. I found a supertrapp exhaust for it and have not been able to find what jets I should be using. So what size should I be looking for and were would I find them. The jets in the carbs seem to be different then what is the standard out there now. Any help would be appreciated.

So what size mains and pilot jet are in there now??..I run a CRF250X Muffler on one of my XL600s and use 125 mains in both carbs  and I think a 65 Pilot,,will confirm that later.

You say the jets are different in the XL than standard,,I take it you mean the main jets. The earlier model twin carb bikes did use different shaped/styled jets than the later models.. What shape are the ones you have in there now??..Are they short and stubby or are they long and skinny??..Picture at all???

It has 125 and 112 jets. They are the short round ones with a straight slot. I put a 65 pilot in it. I am maybe thinking of getting the dynojet kit.

Yep,,So the short stubby ones..You get them from Honda or a place like JetsrUs or Sudco..Dunno what's special about a dynojet kit..If it comes with a complete gasket set for the carbs and all new needles/jets etc then it may be worth buying. If not just buy some individual jets and tune the thing to whatever seems right for your bike.. No doubt way cheaper than a "dynojet kit" whatever that may be..